POS0750 RELATIONSHIP OF CLINICAL AND PATIENT-REPORTED OUTCOMES WITH IMAGING MEASURES OF SYNOVITIS IN JUVENILE ARTHRITIS
Authors: P. Vega Fernandez, K. Rogers, A. Cassedy, A. B. Meyers, T. Ting
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> In children with JIA, the use of outcomes measures for the assessment of disease course and health-related quality of life (HRQL) contribute to improvement of the quality of care provided. However, these subjective outcome measures do not always accurately reflect the inflammatory disease burden and may be influenced by comorbid conditions. Musculoskeletal ultrasound (MSUS) and contrast-enhanced MRI imaging measures of synovitis provide an objective assessment of JIA disease activity. A novel MSUS score for knee arthritis (MSUS-knee score) showed strong correlation with the combined Juvenile Arthritis MRI Scoring (JAMRIS) system in children with JIA<sup>[1]</sup>. <h3>Objectives</h3> To determine the relationship of clinical and patient-reported outcomes (PROs) measures with the MSUS-knee score and the JAMRIS system in children with JIA. <h3>Methods</h3> Children with a diagnosis of JIA who received a MSUS of the knee(s) were enrolled. Data collected included knee physical examination findings, disease activity assessment, the Child Health Assessment Questionnaire (CHAQ) and the pediatric PROMIS Mobility measure (t-score mean 50, standard deviation 10). The following measures were asked to the patients specifically for the examined knee: pain, swelling and morning stiffness. A comprehensive knee MSUS examination was performed on all participants by MSUS certified pediatric rheumatologist. MSUS images were scored by pediatric MSUS experts, who were blinded to clinical information using a semiquantitative scoring system (0-normal to 3-severe)<sup>[1]</sup>. The MSUS-knee score was calculated by adding the abnormal B-mode MSUS scores (score 2 or 3) and the power doppler MSUS scores (score 1 to 3) from the 3 views of MSUS-knee (MSUS-knee score range: 0-15)<sup>[1]</sup>. A subset of participants received an MRI with and without contrast of the knee. MRI of the knee was scored for presence and severity of synovial thickening and joint effusion as per JAMRIS system<sup>[2]</sup>. Associations between clinical and PROs outcome measures and imaging measures were assessed using Spearman's Correlation Coefficient. <h3>Results</h3> Forty-eight children (mean age of 12.1 years) contributed 60 visits. Twenty-four knee MRIs were obtained following MSUS of the knee. Patient reported presence of knee swelling was strongly correlated with the MSUS-knee score and moderately correlated with the JAMRIS system. No other significant statistically associations were found between PROs assessing lower extremity pain and physical function, and overall disease status with imaging measures (Table 1). <h3>Conclusion</h3> Imaging measures of JIA disease activity could provide a more accurate assessment of JIA disease state, given low correlation with commonly used outcome measures. Integration of imaging measures into the shared decision-making in daily clinical practice may improve the quality of medical care. Future studies with a larger population are required. <h3>References</h3> [1]Vega-Fernandez P, et al. Validation of a Novel Ultrasound Scoring System for the Evaluation of Pediatric Knee Arthritis. Arthritis Rheumatol. 2022; 74(9). [2]Hemke, R, et al. Magnetic Resonance Imaging (MRI) of the Knee as an Outcome Measure in Juvenile Idiopathic Arthritis: An OMERACT Reliability Study on MRI Scales. J Rheumatol, 2017. 44:1224-30. <h3>Acknowledgements</h3> To the Center for Clinical &amp; Translational Science &amp; Training (CCTST) at the University of Cincinnati funded by the National Institutes of Health (NIH) Clinical and Translational Science Award (CTSA) program, grant 2UL1TR001425-05A1 and KL2 (2KL2TR001426-05A); and the National Institutes of Arthritis and Musculoskeletal Skin Diseases under Award - Number P30AR076316. <h3>Disclosure of Interests</h3> None Declared.